Rear Light Problems

This technical page includes tips for sorting out your mk1's dodgy rear lights

Recently I had a friend ask for help with the lights on his old car, concerned that for winter driving they just weren’t bright enough. Now compared to modern cars our old Escorts may not seem up to scratch but there are a few things we can do to improve the situation.

Firstly clean the lenses inside and out, a nailbrush and washing up liquid will do the trick and get right into the nooks and crannies.
Now look at how badly scratched your lenses are, years of washing and abrasion will have dulled them. For those who don’t have access to a buffing machine try a good hard rub with T-cut, it works just as well on any hard plastic, and finish with a coat of silicon resin polish. Your lenses should look better for this and will diffuse the light less making them appear a little brighter.

Now check your bulbs, you will be surprised how dirty they can become, wipe them with a clean rag. If the glass appears dark or has a black patch this is the coating from the filament that has evaporated onto the glass, not only does this cut the light output but also the filament is dimmer to start with. The bulb is on the way out so replace it.
If you have disturbed the bulb chances are the contacts could do with a clean. Try to avoid scratching the contacts or using harsh abrasives if at all possible, I strip the bulb holders down and use metal polish.
Next check the wiring, firstly the earth which is often clamped under the mounting of the lamp body, clean all the parts and check the terminal is secure, otherwise replace it. A blob of Vaseline or Waxoil can help protect the terminal when you have finished. Now check the rest of the wiring loom, ensure all the multiplugs in the wiring are clean and fit snugly, most importantly of all check the condition and cleanliness of all your fuses, I replace mine regularly before they begin to corrode.

If you suspect power is being lost in your wiring or across a switch try connecting a voltmeter across the suspect part, for example the switch. Here I would set my meter to the lowest range, about 2 volts, and measure between the live terminal of the switch and the sidelight terminal. Dirty contacts can account for maybe half a volt and this can be enough to make a difference to the performance of your lights, not to mention being a fire hazard! I recently had to rewire the ignition of a Transit after a loose multiplug had caused the wiring to melt.
Perhaps the biggest gain can be made by improving the quality of the reflector, however. My estate car has cast Mazak rear lights which are chrome plated all over, after a good hour polishing them inside and out my tail lights are brilliant, literally (but my fingernails are knackered). I can safely reverse into the garage without reversing lights. Mk1 saloons can also be remedied in the same way.

Vans and MKII saloons are a little more difficult, being plastic which is sprayed silver. I have not yet found a spray paint that performs well enough to use on a reflector; instead I use aluminium body repair tape, the self-adhesive foil type. Cut this into barrel shaped strips and cover the reflector surfaces of all the reflectors, on the MKII also cover the inside of the reflector in the lens (it covers the reversing light bulb) and the galvanised divider between each reflector. Bring this to a high shine using T-cut and finish with a coat of polish again.
By now you should have really nice bright tail lamps, of course the same tricks work on front/rear indicators.
One final tip, if your lenses have faded you could fail the MOT, try putting the colour back in using a Steadler permanent maker of the correct colour on the INSIDE. If this fails I have used Humbrol Clear Red and Orange No.s 1321/2 with an airbrush, again on the inside, to recolour faded lenses. Be careful not to overdo it though.
The author cannot accept responsibility for any claims arising from matter included in this text.

As with all electrical matters, if you have any doubts contact an auto electrician BEFORE starting the job.